As electronic components decrease in size and increase in the power requirements, cooling individual components as well as collections of components will become even more important to ensure proper computing system function moving forward. For example, the size of central processing unit (CPU) dies are miniaturizing at the same time the number of cores, heat dissipation, and thermal design power (TDP) of these dies are increasing. This can result in a higher heat flux from the CPU dies and increases the challenge for thermally managing the CPU. This may be a challenge for legacy cooling solutions to achieve operational performance goals with new components, as system architects seek to lower junction die temperatures in product segments such as desktops, workstations or servers.
Legacy air cooled reference platforms are typically built per American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Class A2. In legacy implementations to support high power dense solutions, liquid-enhanced solutions are typically used where components are cooled by liquid cold plates, and heat is dissipated to the outside air via heat exchangers (HEX) located inside the computer chassis. If the system boundary conditions change, for example if inlet air temperature increases or if workload increases due to turbo operation or overclocking, a CPU may need to be cooled further. In addition, in some legacy systems with multiple components to thermally manage, air or single-phase liquid cooling may be used to cool cold plates connected in series or parallel to cool multiple components. In practice, the second cold plate in the cooling series will be hotter than the first cold plate in the cooling series.